Recordings of 78-RPM Morse Code training records, prepared by the U.S. "Special Service Division, S.O.S., War Department". Manufactured by Allied Record Mfg Co., Hollywood, Calif. (See images of record labels.) There is no date on the recordings but judging by the content ("CORREGIDOR... Get the message through!...") the estimated year of manufacture is probably 1942 or 1943. The recorded material consists of a code aptitude test, introduction to Morse Code letters and... ( 6 reviews ) Topics: AF2Z, Morse Code, code, radio, telegraph, radio telegraph, code practice, 78-RPM, phonograph... Source: 78-RPM phonograph records.